Sara: This weekend we went to Sea World in San Diego.
Tammy: Did you guys have fun?
Sara: Yeah we did! But during the Shamu show the whale splashed water all over us and we got all wet.
Tim: Guess what! Last night I left my car window down and it rained all night!
John: Oh man!
Tim: Yeah, this morning when I got in my car, the inside was all wet!
Meaning: "all wet" is an adjective phrase, so it is used with the verbs "be/get" just like other adjectives. It means to become soaked with water, or to become really wet.